Question

我使用Spring / Spring Boot和Spring MVC和@RestController

我有一个复合模型对象：

public abstract class BaseQuery {

    private final Long characteristicId;

...

}

public abstract class ComparableQuery extends BaseQuery {

    private final Object value;

    private final String comparisonOperator;

...

}

public class GreaterOrEqualQuery extends ComparableQuery {

    public GreaterOrEqualQuery(Long characteristicId, Object value) {
        super(characteristicId, value, ">=");
    }

}

public class EqualQuery extends ComparableQuery {

    public EqualQuery(Long characteristicId, Object value) {
        super(characteristicId, value, "=");
    }

}

public class GreaterQuery extends ComparableQuery {

    public GreaterQuery(Long characteristicId, Object value) {
        super(characteristicId, value, ">");
    }

}

public class CompositQuery extends BaseQuery {

    private final String operator;
    private final BaseQuery[] queries;

    public CompositQuery(Long characteristicId, Operator operator, BaseQuery... queries) {
        super(characteristicId);
        this.operator = operator.value;
        this.queries = queries;
    }

...

}

等

此模型的示例用法类似于：

Set<BaseQuery> queries = new HashSet<>();

BaseQuery megapixelCharacteristicQuery = new CompositQuery(megapixelCharacteristic.getCharacteristicId(), CompositQuery.Operator.AND, new GreaterOrEqualQuery(megapixelCharacteristic.getCharacteristicId(), 10), new LessOrEqualQuery(megapixelCharacteristic.getCharacteristicId(), 50));
queries.add(megapixelCharacteristicQuery);
queries.add(new EqualQuery(androidCharacteristic.getCharacteristicId(), true));

Set<BaseQuery> queries的序列化JSON对象如下所示：

[
   {
      "operator":"AND",
      "queries":[
         {
            "value":10,
            "comparisonOperator":"\u003e\u003d",
            "characteristicId":391
         },
         {
            "value":50,
            "comparisonOperator":"\u003c\u003d",
            "characteristicId":391
         }
      ],
      "characteristicId":391
   },
   {
      "value":true,
      "comparisonOperator":"\u003d",
      "characteristicId":383
   }
]

我必须将此类或类似的JSON从客户端应用程序（AngularJS）传递到我的后端REST API端点，以便获得如上所述的正确反序列化模型（使用CompositQuery或{{1}等相应条目进行设置}）。

现在我的Rest控制器上的Spring应用程序后端逻辑无法使用适当的类正确地反序列化此JSON。

Spring中是否有任何方法可以为此JSON提供一些元信息（或其他内容）以帮助Spring正确反序列化此结构？

Answer 1

你可以使用超类上的jackson注释来实现这一点，如下所示：

import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonSubTypes;
import com.fasterxml.jackson.annotation.JsonSubTypes.Type;
import com.fasterxml.jackson.annotation.JsonTypeInfo;

@JsonTypeInfo(use = JsonTypeInfo.Id.CLASS, include = JsonTypeInfo.As.PROPERTY, property = "javaclass")
@JsonSubTypes({
    @Type(value = GreaterOrEqualQuery.class),
    @Type(value = EqualQuery.class)
    //and so on...
})
public abstract class BaseQuery {
    ...
}

这会将javaclass属性添加到json表示中，这是use = JsonTypeInfo.Id.CLASS的完全限定名称。为了简化此属性的值，请考虑use的{{1}}参数的不同选项（例如@JsonTypeInfo）。

Spring REST JSON序列化/反序列化复合多态类型

1 个答案: